Apparatus for compressing air



S. HUDSON. Apparatus for Compressing Air.

(Kodak) No. 241,984. Patented May 24, I881.

l/lllllllll/II/Ii/I/l/ IJV'V'EJV'TOR Jamuel WEadson,

By his flttorney p 63% 4L 3 UNITED. STATES PATENT OFFICE.

SAMUEL WV. HUDSON, OF HUDSONDALE, PENNSYLVANIA.

APPARATUS FOR COMPRESSIN G AIR.

SPECIFICATION forming part of Letters Patent No. 241,984, dated May 24, 1881,

Application filed January 31, 1881.

To all whom it may concern Be it known that I, SAMUEL W. HUDSON, of Hudsondale, in the county of Carbon and State of Pennsylvania, have invented certain new and useful Improvements in Apparatus for Compressing Air, of which the following is a specification.

The object of my invention is to provide an apparatus for compressing air for various purposes, in which the use of all valves is dispensed with, water being used as a seal for the compressed-air chamber. By this means the construction of my apparatus is rendered very simple, and at the same time the heat generated by the friction of the apparatus and the compression of the air is absorbed by the water, and the temperature of the machine is thus kept comparatively uniform.

A further object of my invention is to reduce the friction of the machine, and thus decrease the power required for working it and the amount of heat generated.

My invention, as above remarked, contemplates the compression of air and the confinement of it in a suitable chamber, from whence it may be drawn for any purpose for which it may be desired, but more particularly contemplates an apparatus by-which airis compressed for the purpose of ventilating mines, which apparatus also serves simultaneously to pump water from the mines.

In the accompanying drawings, Figure l shows an arrangement of' my apparatus for the purpose last above mentioned, and under this organization the machineis driven by any suitable power in any well-known way; and Fig. 2 shows another organization of apparatus worked by a column of water for compressing air for any purpose for which it may be desired.

Referring to Fig. 1, A is a tank or reservoir, in which the water in the mine is-collected, and from which it is to be pumped. A casing or air-chamber, B, is partly submerged in the reservoir, and is provided with cylinders or tubes 0 C. A sprocket-pulley, D, is mounted in bearin gs within the reservoir, beneath the lower ends of the tubes, and a similar pnlley,E, is mounted above the tubes on the same vertical line with the lower pulley. An endless chain, F, passes around these pulleys, through the cylinders G C, and is provided with buckets (ModeL) or piston-heads Gr, of uniform size and shape, similar in general, construction to those used in chain-pumps. The cylinder 0 is the air-compressing cylinder, and G is the pumping-cylinder, as will hereinafter be fully explained. The cylinder 0 is bored of a uniform diameter, and the buckets or piston-heads fitit so that they can freely pass through it with very little friction, and packing may be dispensed with. This cylinder is provided near its lower end with slots or apertures c, for the purpose hereinafter mentioned. The internal diameter of the cylinder 0 is somewhat larger'than the buckets G, except at the point 0, where the cylinder is turned and bored so that the buckets fit it snugly. An opening, H, is made in the casing B, from which opening the compressed air is to be withdrawn and conveyed to the desired point.

The operation of this organization of my apparatus is as follows: The pulley E is driven in the direction of the arrow by suitable power, and as the piston'heads enter the tube 0 the air confined between the heads is carried down the cylinder and escapes through the apertures c and rises within the casing,B. At the same time the water is carried up by the buckets or piston-heads in the tube 0, as is well understood, and discharged through an opening or trough, 1. As the pressure of the air in the casing or air-reservoir B increases the level of the water therein will, of course, fall somewhat, as shown in the drawings; but as the water in the reservoir A is of comparatively large area, its level will not be appreciably affected.

It is obvious that the apertures 0 might be dispensed with and the air allowed to escape into the casing B from the lower end of the air-tube.

By making the air tube 0 of a sufficient length to contain a number of piston-heads I am enabled to use a comparatively loose fit between the cylinder and piston-heads, and thus obviate friction and heat to a great extent, and correspondingly decrease the power required to drive the machine. g

The strip or backward escape of the air past the piston-heads is absorbed or taken up by the airconfined between each pair of pistonheads, and this strip or escape past the piston-heads consequently decreases toward the ICC outer end of the air-tube C until the last piston-head in the tube is reached, where the pressure is practically that of the atmosphere-- that is to say, the air which escapes past the piston-head nearest the openings 0 would tend to compress the air between that piston-head and the next following. There would then be a tendency, on account of this pressure, for the air to escape past the second piston-head, but with a greatly-reduced force, and so on, the pressure diminishinguntilitpraetically reaches that of the atmosphere, as above mentioned. Thus practically all the air which is carried into the tube by the piston-heads entering it is compressed in the chamber B, and I am thus enabled, by the employment of a series of piston-heads, as just described, to dispense with packing in the air-tube and the tight titof the piston-heads in the tube. W here thelevel of the water in the casing I5 is above the apertures c in the air-tube the pressure of air which would cause a strip past the piston-heads would be that due to the compression of the air between the first or innermost piston'head and the water in the tube; but where the level of the water is forced below the apertures in the tube (J the pressure would be that of the air confined in the casing B. In practice it would not be desirable to have the water-level fall below the opening through which the air escapes into the chamber B.

It will be observed, as above remarked, that in my apparatus there are no valves; that the water acts as a perfect seal to the compressedair chamber, preventing the air from escaping either from the bottom of the chamber or through the compressing-tube; thatthe parts of the machinery are caused to pass through the water, which is constantly changing, and thus not only is the construction of the apparatus rendered extremely simple, but the heat, as before mentioned, is absorbed by the water. The water also acts as an abutment, against which the air is compressed.

In practice the air-tube must, of course, be made of considerable length, and 1 only contemplate having the piston-heads tit it part of its length, as will be well understood.

Referring now to Fig. 2, the casing V is made in substantially three parts-an upper dome or compartment, K, constituting the compressed-air chamber, a lower compartment, L, and two tubes, M and N, which connect said compartments. Thepulleysorsprocket-wheels E and D are respectively mounted in bearings in the upper and lower compartments. An endless chain, F, with piston-heads or buckets G, similar to that shown in Fig. 1, passes around the sprocket-wheels and through the tubes M and N, as shown in the drawings. In this organization of my machine the tube N, the endless chain, and buckets constitute a water-motor which furnishes the power to compress the air. The water isintroduced into the casing through a flume, P, and preferably is not allowed to rise above the end k of the tube M in the chamber K. The tube N is of a larger diameter than the piston-heads, except at the point a, from whence it is bored, so that the buckets may exactly fit it. The bored portion of the tube is of a length sufficient to accommodate two of the piston-heads. The column of water introduced through the flume presses down on the piston-head,whichen ters the bored part a of this tube and carries the piston-head down with it, thus causing the sprocket-pulleys to revolve. As one piston-head passes out of the tube N another enters the bored portion of the tube and the operation of the ap paratus continues. The water from the tube N is discharged through the opening R, which is provided with a suitable valve, S. As the water passes under this valve air is admitted at the top, so that the normal pressure of the atmosphere is maintained in the lower compartment of the casing.

The tube M is bored of a uniform diameter throughout its length, so that the piston-heads will fit therein, as described in reference to Fig. 1. As the chain rises through this tube air is carried up by thepiston-heads to the compartment K, the operation being substantially the same as that described in reference to Fig. 1.

The head of water in the flame P may be regulated in accordance with the pressure of the compressed air, and as the pressure of the air in the compartment K increases a greater head of water may be employed. The difference in the height between the point and the flame P allows sufficient; room for the rise and fall of the water-level, due to varying pressures of the air.

The apparatus is started and stopped by the valve S in the discharge-pipe 1t. valve is open the water is all discharged and the operation of the machine continues; but when the valve is closed the water fills the compartment L and the machine is stopped. By leaving the exit or aperture in the compartment K open, so that the air can escape without being compressed, the apparatus just described may be used as an ordinary watermotor.

It might, under some circumstances, be de sirable to make the air-tube similar to the water-tube--that is, with a portion sufficient to accommodate two pistons only, in which the heads would fit tightly, and the remainder of the tube of largerdiameter but the construction shown is preferable, for the reasons before given.

I am aware that fluid abutments and fluid seals are old, and are shown, for instance, in the patent of Osborn, of October 21, 1879, and I therefore make no claim, broadly, to such subject-matter.

I claim as of my own invention- 1. The combination of mechanism for compressing air, a compressed-air chamber, and a fluid abutment within the compressed air chamber against which the air is compressed, which abutment also serves to seal said chamber, substantially as set forth.

2. The combination of a fluid abutment, a

When the IIO compressed-air chamber submerged or partly submerged in the fluid abutment, an air-compressing tube extending from the upper part of the compressed-air chamber to and into the fluid abutment, andmechanism for compressing air by forcing it down the compressingtube into the compressed-air chamber, substantially as described.

3. The combination, substantially as herein set forth, of an air-compressingtube, a series of piston-heads which pass through said tube, mechanism for operating the piston-heads, and a com pressed-air chamber.

4. The combination, substantially as herein set forth, of an air-compressing tube, a series of piston-heads which pass through said tube, mechanism for operating the piston-heads, a compressed-air chamber, and a fluid abutment against which the air is compressed.

5. The combination, substantially as herein set forth, of the compressed-air chamber, the air-compressing tube, the endless chain, piston-heads carried thereby, which piston-heads pass through the air-compressing tube, and a pulley or pulleys over which the endless chain passes.

6. The combination, substantially as herein set forth, of the water-reservoir, the submerged casing constituting the compressed-air chamber, the air-compressing tube, the endless chain, piston-heads carried thereby, and the pulley or pulleys over which the chain passes.

7. The combination, substantially as herein set forth, of the water-reservoir, the compressed-air chamber, the air-compressing tube, the pumping-tube, the endless chain, pistonheads carried thereby, and pulleys over which the endless chain passes.

8. The combination, substantially as herein set forth, of the compressed-air chamber, the air-compressing tube, the water-motor tube, the flume, theendless chain, piston-heads carried thereby, and pulleys over which the chain passes.

9. The combination, substantially as herein set forth, of the compressed-air chamber, the air-compressing tube, the water-motor tube, the flume, the endless chain, piston-heads carried thereby, pulleys over which the chain passes, the'discharge-pipe, and the valve for stopping and starting the apparatus.

In testimony whereof I have hereunto subscribed my name this 29th day of January, A. D. 1881.

SAMUEL W. HUDSON.

Witnesses:

F. BERTOLETTE, L. H. BARBER. 

